Question

Sadly you have become trapped inside the gravity well of a star of mass M = 6.435×10^30kg. At a distance of r0 = 7.543×10^10m from the center of the star you find yourself moving directly towards it at 5.876×10^4m/s (relative to the star). How fast are you moving relative to the star when you inexorably find yourself a distance of rf=1.460×10^10m from its center? (You have no form of mass/energy that you can throw/eject/propel/fire/burn towards the star to slow or prevent your gravitational free-fall towards the star.)

Answer 1

Sorry about not replying last time! I figured this one out though.

The solution can be found by:
vf=√[(v0^2)+(2GM/rf)-(2GM/r0)]

Answer 2

Thanks! Got it.

Answer 3

Did you get #1 and #3?